xref: /openbmc/linux/net/sched/act_api.c (revision 34b7074d)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * net/sched/act_api.c	Packet action API.
4  *
5  * Author:	Jamal Hadi Salim
6  */
7 
8 #include <linux/types.h>
9 #include <linux/kernel.h>
10 #include <linux/string.h>
11 #include <linux/errno.h>
12 #include <linux/slab.h>
13 #include <linux/skbuff.h>
14 #include <linux/init.h>
15 #include <linux/kmod.h>
16 #include <linux/err.h>
17 #include <linux/module.h>
18 #include <net/net_namespace.h>
19 #include <net/sock.h>
20 #include <net/sch_generic.h>
21 #include <net/pkt_cls.h>
22 #include <net/tc_act/tc_pedit.h>
23 #include <net/act_api.h>
24 #include <net/netlink.h>
25 #include <net/flow_offload.h>
26 #include <net/tc_wrapper.h>
27 
28 #ifdef CONFIG_INET
29 DEFINE_STATIC_KEY_FALSE(tcf_frag_xmit_count);
30 EXPORT_SYMBOL_GPL(tcf_frag_xmit_count);
31 #endif
32 
33 int tcf_dev_queue_xmit(struct sk_buff *skb, int (*xmit)(struct sk_buff *skb))
34 {
35 #ifdef CONFIG_INET
36 	if (static_branch_unlikely(&tcf_frag_xmit_count))
37 		return sch_frag_xmit_hook(skb, xmit);
38 #endif
39 
40 	return xmit(skb);
41 }
42 EXPORT_SYMBOL_GPL(tcf_dev_queue_xmit);
43 
44 static void tcf_action_goto_chain_exec(const struct tc_action *a,
45 				       struct tcf_result *res)
46 {
47 	const struct tcf_chain *chain = rcu_dereference_bh(a->goto_chain);
48 
49 	res->goto_tp = rcu_dereference_bh(chain->filter_chain);
50 }
51 
52 static void tcf_free_cookie_rcu(struct rcu_head *p)
53 {
54 	struct tc_cookie *cookie = container_of(p, struct tc_cookie, rcu);
55 
56 	kfree(cookie->data);
57 	kfree(cookie);
58 }
59 
60 static void tcf_set_action_cookie(struct tc_cookie __rcu **old_cookie,
61 				  struct tc_cookie *new_cookie)
62 {
63 	struct tc_cookie *old;
64 
65 	old = xchg((__force struct tc_cookie **)old_cookie, new_cookie);
66 	if (old)
67 		call_rcu(&old->rcu, tcf_free_cookie_rcu);
68 }
69 
70 int tcf_action_check_ctrlact(int action, struct tcf_proto *tp,
71 			     struct tcf_chain **newchain,
72 			     struct netlink_ext_ack *extack)
73 {
74 	int opcode = TC_ACT_EXT_OPCODE(action), ret = -EINVAL;
75 	u32 chain_index;
76 
77 	if (!opcode)
78 		ret = action > TC_ACT_VALUE_MAX ? -EINVAL : 0;
79 	else if (opcode <= TC_ACT_EXT_OPCODE_MAX || action == TC_ACT_UNSPEC)
80 		ret = 0;
81 	if (ret) {
82 		NL_SET_ERR_MSG(extack, "invalid control action");
83 		goto end;
84 	}
85 
86 	if (TC_ACT_EXT_CMP(action, TC_ACT_GOTO_CHAIN)) {
87 		chain_index = action & TC_ACT_EXT_VAL_MASK;
88 		if (!tp || !newchain) {
89 			ret = -EINVAL;
90 			NL_SET_ERR_MSG(extack,
91 				       "can't goto NULL proto/chain");
92 			goto end;
93 		}
94 		*newchain = tcf_chain_get_by_act(tp->chain->block, chain_index);
95 		if (!*newchain) {
96 			ret = -ENOMEM;
97 			NL_SET_ERR_MSG(extack,
98 				       "can't allocate goto_chain");
99 		}
100 	}
101 end:
102 	return ret;
103 }
104 EXPORT_SYMBOL(tcf_action_check_ctrlact);
105 
106 struct tcf_chain *tcf_action_set_ctrlact(struct tc_action *a, int action,
107 					 struct tcf_chain *goto_chain)
108 {
109 	a->tcfa_action = action;
110 	goto_chain = rcu_replace_pointer(a->goto_chain, goto_chain, 1);
111 	return goto_chain;
112 }
113 EXPORT_SYMBOL(tcf_action_set_ctrlact);
114 
115 /* XXX: For standalone actions, we don't need a RCU grace period either, because
116  * actions are always connected to filters and filters are already destroyed in
117  * RCU callbacks, so after a RCU grace period actions are already disconnected
118  * from filters. Readers later can not find us.
119  */
120 static void free_tcf(struct tc_action *p)
121 {
122 	struct tcf_chain *chain = rcu_dereference_protected(p->goto_chain, 1);
123 
124 	free_percpu(p->cpu_bstats);
125 	free_percpu(p->cpu_bstats_hw);
126 	free_percpu(p->cpu_qstats);
127 
128 	tcf_set_action_cookie(&p->act_cookie, NULL);
129 	if (chain)
130 		tcf_chain_put_by_act(chain);
131 
132 	kfree(p);
133 }
134 
135 static void offload_action_hw_count_set(struct tc_action *act,
136 					u32 hw_count)
137 {
138 	act->in_hw_count = hw_count;
139 }
140 
141 static void offload_action_hw_count_inc(struct tc_action *act,
142 					u32 hw_count)
143 {
144 	act->in_hw_count += hw_count;
145 }
146 
147 static void offload_action_hw_count_dec(struct tc_action *act,
148 					u32 hw_count)
149 {
150 	act->in_hw_count = act->in_hw_count > hw_count ?
151 			   act->in_hw_count - hw_count : 0;
152 }
153 
154 static unsigned int tcf_offload_act_num_actions_single(struct tc_action *act)
155 {
156 	if (is_tcf_pedit(act))
157 		return tcf_pedit_nkeys(act);
158 	else
159 		return 1;
160 }
161 
162 static bool tc_act_skip_hw(u32 flags)
163 {
164 	return (flags & TCA_ACT_FLAGS_SKIP_HW) ? true : false;
165 }
166 
167 static bool tc_act_skip_sw(u32 flags)
168 {
169 	return (flags & TCA_ACT_FLAGS_SKIP_SW) ? true : false;
170 }
171 
172 static bool tc_act_in_hw(struct tc_action *act)
173 {
174 	return !!act->in_hw_count;
175 }
176 
177 /* SKIP_HW and SKIP_SW are mutually exclusive flags. */
178 static bool tc_act_flags_valid(u32 flags)
179 {
180 	flags &= TCA_ACT_FLAGS_SKIP_HW | TCA_ACT_FLAGS_SKIP_SW;
181 
182 	return flags ^ (TCA_ACT_FLAGS_SKIP_HW | TCA_ACT_FLAGS_SKIP_SW);
183 }
184 
185 static int offload_action_init(struct flow_offload_action *fl_action,
186 			       struct tc_action *act,
187 			       enum offload_act_command  cmd,
188 			       struct netlink_ext_ack *extack)
189 {
190 	int err;
191 
192 	fl_action->extack = extack;
193 	fl_action->command = cmd;
194 	fl_action->index = act->tcfa_index;
195 
196 	if (act->ops->offload_act_setup) {
197 		spin_lock_bh(&act->tcfa_lock);
198 		err = act->ops->offload_act_setup(act, fl_action, NULL,
199 						  false, extack);
200 		spin_unlock_bh(&act->tcfa_lock);
201 		return err;
202 	}
203 
204 	return -EOPNOTSUPP;
205 }
206 
207 static int tcf_action_offload_cmd_ex(struct flow_offload_action *fl_act,
208 				     u32 *hw_count)
209 {
210 	int err;
211 
212 	err = flow_indr_dev_setup_offload(NULL, NULL, TC_SETUP_ACT,
213 					  fl_act, NULL, NULL);
214 	if (err < 0)
215 		return err;
216 
217 	if (hw_count)
218 		*hw_count = err;
219 
220 	return 0;
221 }
222 
223 static int tcf_action_offload_cmd_cb_ex(struct flow_offload_action *fl_act,
224 					u32 *hw_count,
225 					flow_indr_block_bind_cb_t *cb,
226 					void *cb_priv)
227 {
228 	int err;
229 
230 	err = cb(NULL, NULL, cb_priv, TC_SETUP_ACT, NULL, fl_act, NULL);
231 	if (err < 0)
232 		return err;
233 
234 	if (hw_count)
235 		*hw_count = 1;
236 
237 	return 0;
238 }
239 
240 static int tcf_action_offload_cmd(struct flow_offload_action *fl_act,
241 				  u32 *hw_count,
242 				  flow_indr_block_bind_cb_t *cb,
243 				  void *cb_priv)
244 {
245 	return cb ? tcf_action_offload_cmd_cb_ex(fl_act, hw_count,
246 						 cb, cb_priv) :
247 		    tcf_action_offload_cmd_ex(fl_act, hw_count);
248 }
249 
250 static int tcf_action_offload_add_ex(struct tc_action *action,
251 				     struct netlink_ext_ack *extack,
252 				     flow_indr_block_bind_cb_t *cb,
253 				     void *cb_priv)
254 {
255 	bool skip_sw = tc_act_skip_sw(action->tcfa_flags);
256 	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {
257 		[0] = action,
258 	};
259 	struct flow_offload_action *fl_action;
260 	u32 in_hw_count = 0;
261 	int num, err = 0;
262 
263 	if (tc_act_skip_hw(action->tcfa_flags))
264 		return 0;
265 
266 	num = tcf_offload_act_num_actions_single(action);
267 	fl_action = offload_action_alloc(num);
268 	if (!fl_action)
269 		return -ENOMEM;
270 
271 	err = offload_action_init(fl_action, action, FLOW_ACT_REPLACE, extack);
272 	if (err)
273 		goto fl_err;
274 
275 	err = tc_setup_action(&fl_action->action, actions, extack);
276 	if (err) {
277 		NL_SET_ERR_MSG_MOD(extack,
278 				   "Failed to setup tc actions for offload");
279 		goto fl_err;
280 	}
281 
282 	err = tcf_action_offload_cmd(fl_action, &in_hw_count, cb, cb_priv);
283 	if (!err)
284 		cb ? offload_action_hw_count_inc(action, in_hw_count) :
285 		     offload_action_hw_count_set(action, in_hw_count);
286 
287 	if (skip_sw && !tc_act_in_hw(action))
288 		err = -EINVAL;
289 
290 	tc_cleanup_offload_action(&fl_action->action);
291 
292 fl_err:
293 	kfree(fl_action);
294 
295 	return err;
296 }
297 
298 /* offload the tc action after it is inserted */
299 static int tcf_action_offload_add(struct tc_action *action,
300 				  struct netlink_ext_ack *extack)
301 {
302 	return tcf_action_offload_add_ex(action, extack, NULL, NULL);
303 }
304 
305 int tcf_action_update_hw_stats(struct tc_action *action)
306 {
307 	struct flow_offload_action fl_act = {};
308 	int err;
309 
310 	if (!tc_act_in_hw(action))
311 		return -EOPNOTSUPP;
312 
313 	err = offload_action_init(&fl_act, action, FLOW_ACT_STATS, NULL);
314 	if (err)
315 		return err;
316 
317 	err = tcf_action_offload_cmd(&fl_act, NULL, NULL, NULL);
318 	if (!err) {
319 		preempt_disable();
320 		tcf_action_stats_update(action, fl_act.stats.bytes,
321 					fl_act.stats.pkts,
322 					fl_act.stats.drops,
323 					fl_act.stats.lastused,
324 					true);
325 		preempt_enable();
326 		action->used_hw_stats = fl_act.stats.used_hw_stats;
327 		action->used_hw_stats_valid = true;
328 	} else {
329 		return -EOPNOTSUPP;
330 	}
331 
332 	return 0;
333 }
334 EXPORT_SYMBOL(tcf_action_update_hw_stats);
335 
336 static int tcf_action_offload_del_ex(struct tc_action *action,
337 				     flow_indr_block_bind_cb_t *cb,
338 				     void *cb_priv)
339 {
340 	struct flow_offload_action fl_act = {};
341 	u32 in_hw_count = 0;
342 	int err = 0;
343 
344 	if (!tc_act_in_hw(action))
345 		return 0;
346 
347 	err = offload_action_init(&fl_act, action, FLOW_ACT_DESTROY, NULL);
348 	if (err)
349 		return err;
350 
351 	err = tcf_action_offload_cmd(&fl_act, &in_hw_count, cb, cb_priv);
352 	if (err < 0)
353 		return err;
354 
355 	if (!cb && action->in_hw_count != in_hw_count)
356 		return -EINVAL;
357 
358 	/* do not need to update hw state when deleting action */
359 	if (cb && in_hw_count)
360 		offload_action_hw_count_dec(action, in_hw_count);
361 
362 	return 0;
363 }
364 
365 static int tcf_action_offload_del(struct tc_action *action)
366 {
367 	return tcf_action_offload_del_ex(action, NULL, NULL);
368 }
369 
370 static void tcf_action_cleanup(struct tc_action *p)
371 {
372 	tcf_action_offload_del(p);
373 	if (p->ops->cleanup)
374 		p->ops->cleanup(p);
375 
376 	gen_kill_estimator(&p->tcfa_rate_est);
377 	free_tcf(p);
378 }
379 
380 static int __tcf_action_put(struct tc_action *p, bool bind)
381 {
382 	struct tcf_idrinfo *idrinfo = p->idrinfo;
383 
384 	if (refcount_dec_and_mutex_lock(&p->tcfa_refcnt, &idrinfo->lock)) {
385 		if (bind)
386 			atomic_dec(&p->tcfa_bindcnt);
387 		idr_remove(&idrinfo->action_idr, p->tcfa_index);
388 		mutex_unlock(&idrinfo->lock);
389 
390 		tcf_action_cleanup(p);
391 		return 1;
392 	}
393 
394 	if (bind)
395 		atomic_dec(&p->tcfa_bindcnt);
396 
397 	return 0;
398 }
399 
400 static int __tcf_idr_release(struct tc_action *p, bool bind, bool strict)
401 {
402 	int ret = 0;
403 
404 	/* Release with strict==1 and bind==0 is only called through act API
405 	 * interface (classifiers always bind). Only case when action with
406 	 * positive reference count and zero bind count can exist is when it was
407 	 * also created with act API (unbinding last classifier will destroy the
408 	 * action if it was created by classifier). So only case when bind count
409 	 * can be changed after initial check is when unbound action is
410 	 * destroyed by act API while classifier binds to action with same id
411 	 * concurrently. This result either creation of new action(same behavior
412 	 * as before), or reusing existing action if concurrent process
413 	 * increments reference count before action is deleted. Both scenarios
414 	 * are acceptable.
415 	 */
416 	if (p) {
417 		if (!bind && strict && atomic_read(&p->tcfa_bindcnt) > 0)
418 			return -EPERM;
419 
420 		if (__tcf_action_put(p, bind))
421 			ret = ACT_P_DELETED;
422 	}
423 
424 	return ret;
425 }
426 
427 int tcf_idr_release(struct tc_action *a, bool bind)
428 {
429 	const struct tc_action_ops *ops = a->ops;
430 	int ret;
431 
432 	ret = __tcf_idr_release(a, bind, false);
433 	if (ret == ACT_P_DELETED)
434 		module_put(ops->owner);
435 	return ret;
436 }
437 EXPORT_SYMBOL(tcf_idr_release);
438 
439 static size_t tcf_action_shared_attrs_size(const struct tc_action *act)
440 {
441 	struct tc_cookie *act_cookie;
442 	u32 cookie_len = 0;
443 
444 	rcu_read_lock();
445 	act_cookie = rcu_dereference(act->act_cookie);
446 
447 	if (act_cookie)
448 		cookie_len = nla_total_size(act_cookie->len);
449 	rcu_read_unlock();
450 
451 	return  nla_total_size(0) /* action number nested */
452 		+ nla_total_size(IFNAMSIZ) /* TCA_ACT_KIND */
453 		+ cookie_len /* TCA_ACT_COOKIE */
454 		+ nla_total_size(sizeof(struct nla_bitfield32)) /* TCA_ACT_HW_STATS */
455 		+ nla_total_size(0) /* TCA_ACT_STATS nested */
456 		+ nla_total_size(sizeof(struct nla_bitfield32)) /* TCA_ACT_FLAGS */
457 		/* TCA_STATS_BASIC */
458 		+ nla_total_size_64bit(sizeof(struct gnet_stats_basic))
459 		/* TCA_STATS_PKT64 */
460 		+ nla_total_size_64bit(sizeof(u64))
461 		/* TCA_STATS_QUEUE */
462 		+ nla_total_size_64bit(sizeof(struct gnet_stats_queue))
463 		+ nla_total_size(0) /* TCA_OPTIONS nested */
464 		+ nla_total_size(sizeof(struct tcf_t)); /* TCA_GACT_TM */
465 }
466 
467 static size_t tcf_action_full_attrs_size(size_t sz)
468 {
469 	return NLMSG_HDRLEN                     /* struct nlmsghdr */
470 		+ sizeof(struct tcamsg)
471 		+ nla_total_size(0)             /* TCA_ACT_TAB nested */
472 		+ sz;
473 }
474 
475 static size_t tcf_action_fill_size(const struct tc_action *act)
476 {
477 	size_t sz = tcf_action_shared_attrs_size(act);
478 
479 	if (act->ops->get_fill_size)
480 		return act->ops->get_fill_size(act) + sz;
481 	return sz;
482 }
483 
484 static int
485 tcf_action_dump_terse(struct sk_buff *skb, struct tc_action *a, bool from_act)
486 {
487 	unsigned char *b = skb_tail_pointer(skb);
488 	struct tc_cookie *cookie;
489 
490 	if (nla_put_string(skb, TCA_KIND, a->ops->kind))
491 		goto nla_put_failure;
492 	if (tcf_action_copy_stats(skb, a, 0))
493 		goto nla_put_failure;
494 	if (from_act && nla_put_u32(skb, TCA_ACT_INDEX, a->tcfa_index))
495 		goto nla_put_failure;
496 
497 	rcu_read_lock();
498 	cookie = rcu_dereference(a->act_cookie);
499 	if (cookie) {
500 		if (nla_put(skb, TCA_ACT_COOKIE, cookie->len, cookie->data)) {
501 			rcu_read_unlock();
502 			goto nla_put_failure;
503 		}
504 	}
505 	rcu_read_unlock();
506 
507 	return 0;
508 
509 nla_put_failure:
510 	nlmsg_trim(skb, b);
511 	return -1;
512 }
513 
514 static int tcf_dump_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
515 			   struct netlink_callback *cb)
516 {
517 	int err = 0, index = -1, s_i = 0, n_i = 0;
518 	u32 act_flags = cb->args[2];
519 	unsigned long jiffy_since = cb->args[3];
520 	struct nlattr *nest;
521 	struct idr *idr = &idrinfo->action_idr;
522 	struct tc_action *p;
523 	unsigned long id = 1;
524 	unsigned long tmp;
525 
526 	mutex_lock(&idrinfo->lock);
527 
528 	s_i = cb->args[0];
529 
530 	idr_for_each_entry_ul(idr, p, tmp, id) {
531 		index++;
532 		if (index < s_i)
533 			continue;
534 		if (IS_ERR(p))
535 			continue;
536 
537 		if (jiffy_since &&
538 		    time_after(jiffy_since,
539 			       (unsigned long)p->tcfa_tm.lastuse))
540 			continue;
541 
542 		nest = nla_nest_start_noflag(skb, n_i);
543 		if (!nest) {
544 			index--;
545 			goto nla_put_failure;
546 		}
547 		err = (act_flags & TCA_ACT_FLAG_TERSE_DUMP) ?
548 			tcf_action_dump_terse(skb, p, true) :
549 			tcf_action_dump_1(skb, p, 0, 0);
550 		if (err < 0) {
551 			index--;
552 			nlmsg_trim(skb, nest);
553 			goto done;
554 		}
555 		nla_nest_end(skb, nest);
556 		n_i++;
557 		if (!(act_flags & TCA_ACT_FLAG_LARGE_DUMP_ON) &&
558 		    n_i >= TCA_ACT_MAX_PRIO)
559 			goto done;
560 	}
561 done:
562 	if (index >= 0)
563 		cb->args[0] = index + 1;
564 
565 	mutex_unlock(&idrinfo->lock);
566 	if (n_i) {
567 		if (act_flags & TCA_ACT_FLAG_LARGE_DUMP_ON)
568 			cb->args[1] = n_i;
569 	}
570 	return n_i;
571 
572 nla_put_failure:
573 	nla_nest_cancel(skb, nest);
574 	goto done;
575 }
576 
577 static int tcf_idr_release_unsafe(struct tc_action *p)
578 {
579 	if (atomic_read(&p->tcfa_bindcnt) > 0)
580 		return -EPERM;
581 
582 	if (refcount_dec_and_test(&p->tcfa_refcnt)) {
583 		idr_remove(&p->idrinfo->action_idr, p->tcfa_index);
584 		tcf_action_cleanup(p);
585 		return ACT_P_DELETED;
586 	}
587 
588 	return 0;
589 }
590 
591 static int tcf_del_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
592 			  const struct tc_action_ops *ops,
593 			  struct netlink_ext_ack *extack)
594 {
595 	struct nlattr *nest;
596 	int n_i = 0;
597 	int ret = -EINVAL;
598 	struct idr *idr = &idrinfo->action_idr;
599 	struct tc_action *p;
600 	unsigned long id = 1;
601 	unsigned long tmp;
602 
603 	nest = nla_nest_start_noflag(skb, 0);
604 	if (nest == NULL)
605 		goto nla_put_failure;
606 	if (nla_put_string(skb, TCA_KIND, ops->kind))
607 		goto nla_put_failure;
608 
609 	ret = 0;
610 	mutex_lock(&idrinfo->lock);
611 	idr_for_each_entry_ul(idr, p, tmp, id) {
612 		if (IS_ERR(p))
613 			continue;
614 		ret = tcf_idr_release_unsafe(p);
615 		if (ret == ACT_P_DELETED)
616 			module_put(ops->owner);
617 		else if (ret < 0)
618 			break;
619 		n_i++;
620 	}
621 	mutex_unlock(&idrinfo->lock);
622 	if (ret < 0) {
623 		if (n_i)
624 			NL_SET_ERR_MSG(extack, "Unable to flush all TC actions");
625 		else
626 			goto nla_put_failure;
627 	}
628 
629 	ret = nla_put_u32(skb, TCA_FCNT, n_i);
630 	if (ret)
631 		goto nla_put_failure;
632 	nla_nest_end(skb, nest);
633 
634 	return n_i;
635 nla_put_failure:
636 	nla_nest_cancel(skb, nest);
637 	return ret;
638 }
639 
640 int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
641 		       struct netlink_callback *cb, int type,
642 		       const struct tc_action_ops *ops,
643 		       struct netlink_ext_ack *extack)
644 {
645 	struct tcf_idrinfo *idrinfo = tn->idrinfo;
646 
647 	if (type == RTM_DELACTION) {
648 		return tcf_del_walker(idrinfo, skb, ops, extack);
649 	} else if (type == RTM_GETACTION) {
650 		return tcf_dump_walker(idrinfo, skb, cb);
651 	} else {
652 		WARN(1, "tcf_generic_walker: unknown command %d\n", type);
653 		NL_SET_ERR_MSG(extack, "tcf_generic_walker: unknown command");
654 		return -EINVAL;
655 	}
656 }
657 EXPORT_SYMBOL(tcf_generic_walker);
658 
659 int tcf_idr_search(struct tc_action_net *tn, struct tc_action **a, u32 index)
660 {
661 	struct tcf_idrinfo *idrinfo = tn->idrinfo;
662 	struct tc_action *p;
663 
664 	mutex_lock(&idrinfo->lock);
665 	p = idr_find(&idrinfo->action_idr, index);
666 	if (IS_ERR(p))
667 		p = NULL;
668 	else if (p)
669 		refcount_inc(&p->tcfa_refcnt);
670 	mutex_unlock(&idrinfo->lock);
671 
672 	if (p) {
673 		*a = p;
674 		return true;
675 	}
676 	return false;
677 }
678 EXPORT_SYMBOL(tcf_idr_search);
679 
680 static int __tcf_generic_walker(struct net *net, struct sk_buff *skb,
681 				struct netlink_callback *cb, int type,
682 				const struct tc_action_ops *ops,
683 				struct netlink_ext_ack *extack)
684 {
685 	struct tc_action_net *tn = net_generic(net, ops->net_id);
686 
687 	if (unlikely(ops->walk))
688 		return ops->walk(net, skb, cb, type, ops, extack);
689 
690 	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
691 }
692 
693 static int __tcf_idr_search(struct net *net,
694 			    const struct tc_action_ops *ops,
695 			    struct tc_action **a, u32 index)
696 {
697 	struct tc_action_net *tn = net_generic(net, ops->net_id);
698 
699 	if (unlikely(ops->lookup))
700 		return ops->lookup(net, a, index);
701 
702 	return tcf_idr_search(tn, a, index);
703 }
704 
705 static int tcf_idr_delete_index(struct tcf_idrinfo *idrinfo, u32 index)
706 {
707 	struct tc_action *p;
708 	int ret = 0;
709 
710 	mutex_lock(&idrinfo->lock);
711 	p = idr_find(&idrinfo->action_idr, index);
712 	if (!p) {
713 		mutex_unlock(&idrinfo->lock);
714 		return -ENOENT;
715 	}
716 
717 	if (!atomic_read(&p->tcfa_bindcnt)) {
718 		if (refcount_dec_and_test(&p->tcfa_refcnt)) {
719 			struct module *owner = p->ops->owner;
720 
721 			WARN_ON(p != idr_remove(&idrinfo->action_idr,
722 						p->tcfa_index));
723 			mutex_unlock(&idrinfo->lock);
724 
725 			tcf_action_cleanup(p);
726 			module_put(owner);
727 			return 0;
728 		}
729 		ret = 0;
730 	} else {
731 		ret = -EPERM;
732 	}
733 
734 	mutex_unlock(&idrinfo->lock);
735 	return ret;
736 }
737 
738 int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est,
739 		   struct tc_action **a, const struct tc_action_ops *ops,
740 		   int bind, bool cpustats, u32 flags)
741 {
742 	struct tc_action *p = kzalloc(ops->size, GFP_KERNEL);
743 	struct tcf_idrinfo *idrinfo = tn->idrinfo;
744 	int err = -ENOMEM;
745 
746 	if (unlikely(!p))
747 		return -ENOMEM;
748 	refcount_set(&p->tcfa_refcnt, 1);
749 	if (bind)
750 		atomic_set(&p->tcfa_bindcnt, 1);
751 
752 	if (cpustats) {
753 		p->cpu_bstats = netdev_alloc_pcpu_stats(struct gnet_stats_basic_sync);
754 		if (!p->cpu_bstats)
755 			goto err1;
756 		p->cpu_bstats_hw = netdev_alloc_pcpu_stats(struct gnet_stats_basic_sync);
757 		if (!p->cpu_bstats_hw)
758 			goto err2;
759 		p->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
760 		if (!p->cpu_qstats)
761 			goto err3;
762 	}
763 	gnet_stats_basic_sync_init(&p->tcfa_bstats);
764 	gnet_stats_basic_sync_init(&p->tcfa_bstats_hw);
765 	spin_lock_init(&p->tcfa_lock);
766 	p->tcfa_index = index;
767 	p->tcfa_tm.install = jiffies;
768 	p->tcfa_tm.lastuse = jiffies;
769 	p->tcfa_tm.firstuse = 0;
770 	p->tcfa_flags = flags;
771 	if (est) {
772 		err = gen_new_estimator(&p->tcfa_bstats, p->cpu_bstats,
773 					&p->tcfa_rate_est,
774 					&p->tcfa_lock, false, est);
775 		if (err)
776 			goto err4;
777 	}
778 
779 	p->idrinfo = idrinfo;
780 	__module_get(ops->owner);
781 	p->ops = ops;
782 	*a = p;
783 	return 0;
784 err4:
785 	free_percpu(p->cpu_qstats);
786 err3:
787 	free_percpu(p->cpu_bstats_hw);
788 err2:
789 	free_percpu(p->cpu_bstats);
790 err1:
791 	kfree(p);
792 	return err;
793 }
794 EXPORT_SYMBOL(tcf_idr_create);
795 
796 int tcf_idr_create_from_flags(struct tc_action_net *tn, u32 index,
797 			      struct nlattr *est, struct tc_action **a,
798 			      const struct tc_action_ops *ops, int bind,
799 			      u32 flags)
800 {
801 	/* Set cpustats according to actions flags. */
802 	return tcf_idr_create(tn, index, est, a, ops, bind,
803 			      !(flags & TCA_ACT_FLAGS_NO_PERCPU_STATS), flags);
804 }
805 EXPORT_SYMBOL(tcf_idr_create_from_flags);
806 
807 /* Cleanup idr index that was allocated but not initialized. */
808 
809 void tcf_idr_cleanup(struct tc_action_net *tn, u32 index)
810 {
811 	struct tcf_idrinfo *idrinfo = tn->idrinfo;
812 
813 	mutex_lock(&idrinfo->lock);
814 	/* Remove ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
815 	WARN_ON(!IS_ERR(idr_remove(&idrinfo->action_idr, index)));
816 	mutex_unlock(&idrinfo->lock);
817 }
818 EXPORT_SYMBOL(tcf_idr_cleanup);
819 
820 /* Check if action with specified index exists. If actions is found, increments
821  * its reference and bind counters, and return 1. Otherwise insert temporary
822  * error pointer (to prevent concurrent users from inserting actions with same
823  * index) and return 0.
824  */
825 
826 int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index,
827 			struct tc_action **a, int bind)
828 {
829 	struct tcf_idrinfo *idrinfo = tn->idrinfo;
830 	struct tc_action *p;
831 	int ret;
832 
833 again:
834 	mutex_lock(&idrinfo->lock);
835 	if (*index) {
836 		p = idr_find(&idrinfo->action_idr, *index);
837 		if (IS_ERR(p)) {
838 			/* This means that another process allocated
839 			 * index but did not assign the pointer yet.
840 			 */
841 			mutex_unlock(&idrinfo->lock);
842 			goto again;
843 		}
844 
845 		if (p) {
846 			refcount_inc(&p->tcfa_refcnt);
847 			if (bind)
848 				atomic_inc(&p->tcfa_bindcnt);
849 			*a = p;
850 			ret = 1;
851 		} else {
852 			*a = NULL;
853 			ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
854 					    *index, GFP_KERNEL);
855 			if (!ret)
856 				idr_replace(&idrinfo->action_idr,
857 					    ERR_PTR(-EBUSY), *index);
858 		}
859 	} else {
860 		*index = 1;
861 		*a = NULL;
862 		ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
863 				    UINT_MAX, GFP_KERNEL);
864 		if (!ret)
865 			idr_replace(&idrinfo->action_idr, ERR_PTR(-EBUSY),
866 				    *index);
867 	}
868 	mutex_unlock(&idrinfo->lock);
869 	return ret;
870 }
871 EXPORT_SYMBOL(tcf_idr_check_alloc);
872 
873 void tcf_idrinfo_destroy(const struct tc_action_ops *ops,
874 			 struct tcf_idrinfo *idrinfo)
875 {
876 	struct idr *idr = &idrinfo->action_idr;
877 	struct tc_action *p;
878 	int ret;
879 	unsigned long id = 1;
880 	unsigned long tmp;
881 
882 	idr_for_each_entry_ul(idr, p, tmp, id) {
883 		ret = __tcf_idr_release(p, false, true);
884 		if (ret == ACT_P_DELETED)
885 			module_put(ops->owner);
886 		else if (ret < 0)
887 			return;
888 	}
889 	idr_destroy(&idrinfo->action_idr);
890 }
891 EXPORT_SYMBOL(tcf_idrinfo_destroy);
892 
893 static LIST_HEAD(act_base);
894 static DEFINE_RWLOCK(act_mod_lock);
895 /* since act ops id is stored in pernet subsystem list,
896  * then there is no way to walk through only all the action
897  * subsystem, so we keep tc action pernet ops id for
898  * reoffload to walk through.
899  */
900 static LIST_HEAD(act_pernet_id_list);
901 static DEFINE_MUTEX(act_id_mutex);
902 struct tc_act_pernet_id {
903 	struct list_head list;
904 	unsigned int id;
905 };
906 
907 static int tcf_pernet_add_id_list(unsigned int id)
908 {
909 	struct tc_act_pernet_id *id_ptr;
910 	int ret = 0;
911 
912 	mutex_lock(&act_id_mutex);
913 	list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
914 		if (id_ptr->id == id) {
915 			ret = -EEXIST;
916 			goto err_out;
917 		}
918 	}
919 
920 	id_ptr = kzalloc(sizeof(*id_ptr), GFP_KERNEL);
921 	if (!id_ptr) {
922 		ret = -ENOMEM;
923 		goto err_out;
924 	}
925 	id_ptr->id = id;
926 
927 	list_add_tail(&id_ptr->list, &act_pernet_id_list);
928 
929 err_out:
930 	mutex_unlock(&act_id_mutex);
931 	return ret;
932 }
933 
934 static void tcf_pernet_del_id_list(unsigned int id)
935 {
936 	struct tc_act_pernet_id *id_ptr;
937 
938 	mutex_lock(&act_id_mutex);
939 	list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
940 		if (id_ptr->id == id) {
941 			list_del(&id_ptr->list);
942 			kfree(id_ptr);
943 			break;
944 		}
945 	}
946 	mutex_unlock(&act_id_mutex);
947 }
948 
949 int tcf_register_action(struct tc_action_ops *act,
950 			struct pernet_operations *ops)
951 {
952 	struct tc_action_ops *a;
953 	int ret;
954 
955 	if (!act->act || !act->dump || !act->init)
956 		return -EINVAL;
957 
958 	/* We have to register pernet ops before making the action ops visible,
959 	 * otherwise tcf_action_init_1() could get a partially initialized
960 	 * netns.
961 	 */
962 	ret = register_pernet_subsys(ops);
963 	if (ret)
964 		return ret;
965 
966 	if (ops->id) {
967 		ret = tcf_pernet_add_id_list(*ops->id);
968 		if (ret)
969 			goto err_id;
970 	}
971 
972 	write_lock(&act_mod_lock);
973 	list_for_each_entry(a, &act_base, head) {
974 		if (act->id == a->id || (strcmp(act->kind, a->kind) == 0)) {
975 			ret = -EEXIST;
976 			goto err_out;
977 		}
978 	}
979 	list_add_tail(&act->head, &act_base);
980 	write_unlock(&act_mod_lock);
981 
982 	return 0;
983 
984 err_out:
985 	write_unlock(&act_mod_lock);
986 	if (ops->id)
987 		tcf_pernet_del_id_list(*ops->id);
988 err_id:
989 	unregister_pernet_subsys(ops);
990 	return ret;
991 }
992 EXPORT_SYMBOL(tcf_register_action);
993 
994 int tcf_unregister_action(struct tc_action_ops *act,
995 			  struct pernet_operations *ops)
996 {
997 	struct tc_action_ops *a;
998 	int err = -ENOENT;
999 
1000 	write_lock(&act_mod_lock);
1001 	list_for_each_entry(a, &act_base, head) {
1002 		if (a == act) {
1003 			list_del(&act->head);
1004 			err = 0;
1005 			break;
1006 		}
1007 	}
1008 	write_unlock(&act_mod_lock);
1009 	if (!err) {
1010 		unregister_pernet_subsys(ops);
1011 		if (ops->id)
1012 			tcf_pernet_del_id_list(*ops->id);
1013 	}
1014 	return err;
1015 }
1016 EXPORT_SYMBOL(tcf_unregister_action);
1017 
1018 /* lookup by name */
1019 static struct tc_action_ops *tc_lookup_action_n(char *kind)
1020 {
1021 	struct tc_action_ops *a, *res = NULL;
1022 
1023 	if (kind) {
1024 		read_lock(&act_mod_lock);
1025 		list_for_each_entry(a, &act_base, head) {
1026 			if (strcmp(kind, a->kind) == 0) {
1027 				if (try_module_get(a->owner))
1028 					res = a;
1029 				break;
1030 			}
1031 		}
1032 		read_unlock(&act_mod_lock);
1033 	}
1034 	return res;
1035 }
1036 
1037 /* lookup by nlattr */
1038 static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
1039 {
1040 	struct tc_action_ops *a, *res = NULL;
1041 
1042 	if (kind) {
1043 		read_lock(&act_mod_lock);
1044 		list_for_each_entry(a, &act_base, head) {
1045 			if (nla_strcmp(kind, a->kind) == 0) {
1046 				if (try_module_get(a->owner))
1047 					res = a;
1048 				break;
1049 			}
1050 		}
1051 		read_unlock(&act_mod_lock);
1052 	}
1053 	return res;
1054 }
1055 
1056 /*TCA_ACT_MAX_PRIO is 32, there count up to 32 */
1057 #define TCA_ACT_MAX_PRIO_MASK 0x1FF
1058 int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
1059 		    int nr_actions, struct tcf_result *res)
1060 {
1061 	u32 jmp_prgcnt = 0;
1062 	u32 jmp_ttl = TCA_ACT_MAX_PRIO; /*matches actions per filter */
1063 	int i;
1064 	int ret = TC_ACT_OK;
1065 
1066 	if (skb_skip_tc_classify(skb))
1067 		return TC_ACT_OK;
1068 
1069 restart_act_graph:
1070 	for (i = 0; i < nr_actions; i++) {
1071 		const struct tc_action *a = actions[i];
1072 		int repeat_ttl;
1073 
1074 		if (jmp_prgcnt > 0) {
1075 			jmp_prgcnt -= 1;
1076 			continue;
1077 		}
1078 
1079 		if (tc_act_skip_sw(a->tcfa_flags))
1080 			continue;
1081 
1082 		repeat_ttl = 32;
1083 repeat:
1084 		ret = tc_act(skb, a, res);
1085 		if (unlikely(ret == TC_ACT_REPEAT)) {
1086 			if (--repeat_ttl != 0)
1087 				goto repeat;
1088 			/* suspicious opcode, stop pipeline */
1089 			net_warn_ratelimited("TC_ACT_REPEAT abuse ?\n");
1090 			return TC_ACT_OK;
1091 		}
1092 		if (TC_ACT_EXT_CMP(ret, TC_ACT_JUMP)) {
1093 			jmp_prgcnt = ret & TCA_ACT_MAX_PRIO_MASK;
1094 			if (!jmp_prgcnt || (jmp_prgcnt > nr_actions)) {
1095 				/* faulty opcode, stop pipeline */
1096 				return TC_ACT_OK;
1097 			} else {
1098 				jmp_ttl -= 1;
1099 				if (jmp_ttl > 0)
1100 					goto restart_act_graph;
1101 				else /* faulty graph, stop pipeline */
1102 					return TC_ACT_OK;
1103 			}
1104 		} else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
1105 			if (unlikely(!rcu_access_pointer(a->goto_chain))) {
1106 				net_warn_ratelimited("can't go to NULL chain!\n");
1107 				return TC_ACT_SHOT;
1108 			}
1109 			tcf_action_goto_chain_exec(a, res);
1110 		}
1111 
1112 		if (ret != TC_ACT_PIPE)
1113 			break;
1114 	}
1115 
1116 	return ret;
1117 }
1118 EXPORT_SYMBOL(tcf_action_exec);
1119 
1120 int tcf_action_destroy(struct tc_action *actions[], int bind)
1121 {
1122 	const struct tc_action_ops *ops;
1123 	struct tc_action *a;
1124 	int ret = 0, i;
1125 
1126 	for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1127 		a = actions[i];
1128 		actions[i] = NULL;
1129 		ops = a->ops;
1130 		ret = __tcf_idr_release(a, bind, true);
1131 		if (ret == ACT_P_DELETED)
1132 			module_put(ops->owner);
1133 		else if (ret < 0)
1134 			return ret;
1135 	}
1136 	return ret;
1137 }
1138 
1139 static int tcf_action_put(struct tc_action *p)
1140 {
1141 	return __tcf_action_put(p, false);
1142 }
1143 
1144 /* Put all actions in this array, skip those NULL's. */
1145 static void tcf_action_put_many(struct tc_action *actions[])
1146 {
1147 	int i;
1148 
1149 	for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
1150 		struct tc_action *a = actions[i];
1151 		const struct tc_action_ops *ops;
1152 
1153 		if (!a)
1154 			continue;
1155 		ops = a->ops;
1156 		if (tcf_action_put(a))
1157 			module_put(ops->owner);
1158 	}
1159 }
1160 
1161 int
1162 tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
1163 {
1164 	return a->ops->dump(skb, a, bind, ref);
1165 }
1166 
1167 int
1168 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
1169 {
1170 	int err = -EINVAL;
1171 	unsigned char *b = skb_tail_pointer(skb);
1172 	struct nlattr *nest;
1173 	u32 flags;
1174 
1175 	if (tcf_action_dump_terse(skb, a, false))
1176 		goto nla_put_failure;
1177 
1178 	if (a->hw_stats != TCA_ACT_HW_STATS_ANY &&
1179 	    nla_put_bitfield32(skb, TCA_ACT_HW_STATS,
1180 			       a->hw_stats, TCA_ACT_HW_STATS_ANY))
1181 		goto nla_put_failure;
1182 
1183 	if (a->used_hw_stats_valid &&
1184 	    nla_put_bitfield32(skb, TCA_ACT_USED_HW_STATS,
1185 			       a->used_hw_stats, TCA_ACT_HW_STATS_ANY))
1186 		goto nla_put_failure;
1187 
1188 	flags = a->tcfa_flags & TCA_ACT_FLAGS_USER_MASK;
1189 	if (flags &&
1190 	    nla_put_bitfield32(skb, TCA_ACT_FLAGS,
1191 			       flags, flags))
1192 		goto nla_put_failure;
1193 
1194 	if (nla_put_u32(skb, TCA_ACT_IN_HW_COUNT, a->in_hw_count))
1195 		goto nla_put_failure;
1196 
1197 	nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
1198 	if (nest == NULL)
1199 		goto nla_put_failure;
1200 	err = tcf_action_dump_old(skb, a, bind, ref);
1201 	if (err > 0) {
1202 		nla_nest_end(skb, nest);
1203 		return err;
1204 	}
1205 
1206 nla_put_failure:
1207 	nlmsg_trim(skb, b);
1208 	return -1;
1209 }
1210 EXPORT_SYMBOL(tcf_action_dump_1);
1211 
1212 int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[],
1213 		    int bind, int ref, bool terse)
1214 {
1215 	struct tc_action *a;
1216 	int err = -EINVAL, i;
1217 	struct nlattr *nest;
1218 
1219 	for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1220 		a = actions[i];
1221 		nest = nla_nest_start_noflag(skb, i + 1);
1222 		if (nest == NULL)
1223 			goto nla_put_failure;
1224 		err = terse ? tcf_action_dump_terse(skb, a, false) :
1225 			tcf_action_dump_1(skb, a, bind, ref);
1226 		if (err < 0)
1227 			goto errout;
1228 		nla_nest_end(skb, nest);
1229 	}
1230 
1231 	return 0;
1232 
1233 nla_put_failure:
1234 	err = -EINVAL;
1235 errout:
1236 	nla_nest_cancel(skb, nest);
1237 	return err;
1238 }
1239 
1240 static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb)
1241 {
1242 	struct tc_cookie *c = kzalloc(sizeof(*c), GFP_KERNEL);
1243 	if (!c)
1244 		return NULL;
1245 
1246 	c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL);
1247 	if (!c->data) {
1248 		kfree(c);
1249 		return NULL;
1250 	}
1251 	c->len = nla_len(tb[TCA_ACT_COOKIE]);
1252 
1253 	return c;
1254 }
1255 
1256 static u8 tcf_action_hw_stats_get(struct nlattr *hw_stats_attr)
1257 {
1258 	struct nla_bitfield32 hw_stats_bf;
1259 
1260 	/* If the user did not pass the attr, that means he does
1261 	 * not care about the type. Return "any" in that case
1262 	 * which is setting on all supported types.
1263 	 */
1264 	if (!hw_stats_attr)
1265 		return TCA_ACT_HW_STATS_ANY;
1266 	hw_stats_bf = nla_get_bitfield32(hw_stats_attr);
1267 	return hw_stats_bf.value;
1268 }
1269 
1270 static const struct nla_policy tcf_action_policy[TCA_ACT_MAX + 1] = {
1271 	[TCA_ACT_KIND]		= { .type = NLA_STRING },
1272 	[TCA_ACT_INDEX]		= { .type = NLA_U32 },
1273 	[TCA_ACT_COOKIE]	= { .type = NLA_BINARY,
1274 				    .len = TC_COOKIE_MAX_SIZE },
1275 	[TCA_ACT_OPTIONS]	= { .type = NLA_NESTED },
1276 	[TCA_ACT_FLAGS]		= NLA_POLICY_BITFIELD32(TCA_ACT_FLAGS_NO_PERCPU_STATS |
1277 							TCA_ACT_FLAGS_SKIP_HW |
1278 							TCA_ACT_FLAGS_SKIP_SW),
1279 	[TCA_ACT_HW_STATS]	= NLA_POLICY_BITFIELD32(TCA_ACT_HW_STATS_ANY),
1280 };
1281 
1282 void tcf_idr_insert_many(struct tc_action *actions[])
1283 {
1284 	int i;
1285 
1286 	for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
1287 		struct tc_action *a = actions[i];
1288 		struct tcf_idrinfo *idrinfo;
1289 
1290 		if (!a)
1291 			continue;
1292 		idrinfo = a->idrinfo;
1293 		mutex_lock(&idrinfo->lock);
1294 		/* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc if
1295 		 * it is just created, otherwise this is just a nop.
1296 		 */
1297 		idr_replace(&idrinfo->action_idr, a, a->tcfa_index);
1298 		mutex_unlock(&idrinfo->lock);
1299 	}
1300 }
1301 
1302 struct tc_action_ops *tc_action_load_ops(struct nlattr *nla, bool police,
1303 					 bool rtnl_held,
1304 					 struct netlink_ext_ack *extack)
1305 {
1306 	struct nlattr *tb[TCA_ACT_MAX + 1];
1307 	struct tc_action_ops *a_o;
1308 	char act_name[IFNAMSIZ];
1309 	struct nlattr *kind;
1310 	int err;
1311 
1312 	if (!police) {
1313 		err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1314 						  tcf_action_policy, extack);
1315 		if (err < 0)
1316 			return ERR_PTR(err);
1317 		err = -EINVAL;
1318 		kind = tb[TCA_ACT_KIND];
1319 		if (!kind) {
1320 			NL_SET_ERR_MSG(extack, "TC action kind must be specified");
1321 			return ERR_PTR(err);
1322 		}
1323 		if (nla_strscpy(act_name, kind, IFNAMSIZ) < 0) {
1324 			NL_SET_ERR_MSG(extack, "TC action name too long");
1325 			return ERR_PTR(err);
1326 		}
1327 	} else {
1328 		if (strlcpy(act_name, "police", IFNAMSIZ) >= IFNAMSIZ) {
1329 			NL_SET_ERR_MSG(extack, "TC action name too long");
1330 			return ERR_PTR(-EINVAL);
1331 		}
1332 	}
1333 
1334 	a_o = tc_lookup_action_n(act_name);
1335 	if (a_o == NULL) {
1336 #ifdef CONFIG_MODULES
1337 		if (rtnl_held)
1338 			rtnl_unlock();
1339 		request_module("act_%s", act_name);
1340 		if (rtnl_held)
1341 			rtnl_lock();
1342 
1343 		a_o = tc_lookup_action_n(act_name);
1344 
1345 		/* We dropped the RTNL semaphore in order to
1346 		 * perform the module load.  So, even if we
1347 		 * succeeded in loading the module we have to
1348 		 * tell the caller to replay the request.  We
1349 		 * indicate this using -EAGAIN.
1350 		 */
1351 		if (a_o != NULL) {
1352 			module_put(a_o->owner);
1353 			return ERR_PTR(-EAGAIN);
1354 		}
1355 #endif
1356 		NL_SET_ERR_MSG(extack, "Failed to load TC action module");
1357 		return ERR_PTR(-ENOENT);
1358 	}
1359 
1360 	return a_o;
1361 }
1362 
1363 struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
1364 				    struct nlattr *nla, struct nlattr *est,
1365 				    struct tc_action_ops *a_o, int *init_res,
1366 				    u32 flags, struct netlink_ext_ack *extack)
1367 {
1368 	bool police = flags & TCA_ACT_FLAGS_POLICE;
1369 	struct nla_bitfield32 userflags = { 0, 0 };
1370 	u8 hw_stats = TCA_ACT_HW_STATS_ANY;
1371 	struct nlattr *tb[TCA_ACT_MAX + 1];
1372 	struct tc_cookie *cookie = NULL;
1373 	struct tc_action *a;
1374 	int err;
1375 
1376 	/* backward compatibility for policer */
1377 	if (!police) {
1378 		err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1379 						  tcf_action_policy, extack);
1380 		if (err < 0)
1381 			return ERR_PTR(err);
1382 		if (tb[TCA_ACT_COOKIE]) {
1383 			cookie = nla_memdup_cookie(tb);
1384 			if (!cookie) {
1385 				NL_SET_ERR_MSG(extack, "No memory to generate TC cookie");
1386 				err = -ENOMEM;
1387 				goto err_out;
1388 			}
1389 		}
1390 		hw_stats = tcf_action_hw_stats_get(tb[TCA_ACT_HW_STATS]);
1391 		if (tb[TCA_ACT_FLAGS]) {
1392 			userflags = nla_get_bitfield32(tb[TCA_ACT_FLAGS]);
1393 			if (!tc_act_flags_valid(userflags.value)) {
1394 				err = -EINVAL;
1395 				goto err_out;
1396 			}
1397 		}
1398 
1399 		err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, tp,
1400 				userflags.value | flags, extack);
1401 	} else {
1402 		err = a_o->init(net, nla, est, &a, tp, userflags.value | flags,
1403 				extack);
1404 	}
1405 	if (err < 0)
1406 		goto err_out;
1407 	*init_res = err;
1408 
1409 	if (!police && tb[TCA_ACT_COOKIE])
1410 		tcf_set_action_cookie(&a->act_cookie, cookie);
1411 
1412 	if (!police)
1413 		a->hw_stats = hw_stats;
1414 
1415 	return a;
1416 
1417 err_out:
1418 	if (cookie) {
1419 		kfree(cookie->data);
1420 		kfree(cookie);
1421 	}
1422 	return ERR_PTR(err);
1423 }
1424 
1425 static bool tc_act_bind(u32 flags)
1426 {
1427 	return !!(flags & TCA_ACT_FLAGS_BIND);
1428 }
1429 
1430 /* Returns numbers of initialized actions or negative error. */
1431 
1432 int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
1433 		    struct nlattr *est, struct tc_action *actions[],
1434 		    int init_res[], size_t *attr_size,
1435 		    u32 flags, u32 fl_flags,
1436 		    struct netlink_ext_ack *extack)
1437 {
1438 	struct tc_action_ops *ops[TCA_ACT_MAX_PRIO] = {};
1439 	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1440 	struct tc_action *act;
1441 	size_t sz = 0;
1442 	int err;
1443 	int i;
1444 
1445 	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
1446 					  extack);
1447 	if (err < 0)
1448 		return err;
1449 
1450 	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1451 		struct tc_action_ops *a_o;
1452 
1453 		a_o = tc_action_load_ops(tb[i], flags & TCA_ACT_FLAGS_POLICE,
1454 					 !(flags & TCA_ACT_FLAGS_NO_RTNL),
1455 					 extack);
1456 		if (IS_ERR(a_o)) {
1457 			err = PTR_ERR(a_o);
1458 			goto err_mod;
1459 		}
1460 		ops[i - 1] = a_o;
1461 	}
1462 
1463 	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1464 		act = tcf_action_init_1(net, tp, tb[i], est, ops[i - 1],
1465 					&init_res[i - 1], flags, extack);
1466 		if (IS_ERR(act)) {
1467 			err = PTR_ERR(act);
1468 			goto err;
1469 		}
1470 		sz += tcf_action_fill_size(act);
1471 		/* Start from index 0 */
1472 		actions[i - 1] = act;
1473 		if (tc_act_bind(flags)) {
1474 			bool skip_sw = tc_skip_sw(fl_flags);
1475 			bool skip_hw = tc_skip_hw(fl_flags);
1476 
1477 			if (tc_act_bind(act->tcfa_flags))
1478 				continue;
1479 			if (skip_sw != tc_act_skip_sw(act->tcfa_flags) ||
1480 			    skip_hw != tc_act_skip_hw(act->tcfa_flags)) {
1481 				NL_SET_ERR_MSG(extack,
1482 					       "Mismatch between action and filter offload flags");
1483 				err = -EINVAL;
1484 				goto err;
1485 			}
1486 		} else {
1487 			err = tcf_action_offload_add(act, extack);
1488 			if (tc_act_skip_sw(act->tcfa_flags) && err)
1489 				goto err;
1490 		}
1491 	}
1492 
1493 	/* We have to commit them all together, because if any error happened in
1494 	 * between, we could not handle the failure gracefully.
1495 	 */
1496 	tcf_idr_insert_many(actions);
1497 
1498 	*attr_size = tcf_action_full_attrs_size(sz);
1499 	err = i - 1;
1500 	goto err_mod;
1501 
1502 err:
1503 	tcf_action_destroy(actions, flags & TCA_ACT_FLAGS_BIND);
1504 err_mod:
1505 	for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
1506 		if (ops[i])
1507 			module_put(ops[i]->owner);
1508 	}
1509 	return err;
1510 }
1511 
1512 void tcf_action_update_stats(struct tc_action *a, u64 bytes, u64 packets,
1513 			     u64 drops, bool hw)
1514 {
1515 	if (a->cpu_bstats) {
1516 		_bstats_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
1517 
1518 		this_cpu_ptr(a->cpu_qstats)->drops += drops;
1519 
1520 		if (hw)
1521 			_bstats_update(this_cpu_ptr(a->cpu_bstats_hw),
1522 				       bytes, packets);
1523 		return;
1524 	}
1525 
1526 	_bstats_update(&a->tcfa_bstats, bytes, packets);
1527 	a->tcfa_qstats.drops += drops;
1528 	if (hw)
1529 		_bstats_update(&a->tcfa_bstats_hw, bytes, packets);
1530 }
1531 EXPORT_SYMBOL(tcf_action_update_stats);
1532 
1533 int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
1534 			  int compat_mode)
1535 {
1536 	int err = 0;
1537 	struct gnet_dump d;
1538 
1539 	if (p == NULL)
1540 		goto errout;
1541 
1542 	/* update hw stats for this action */
1543 	tcf_action_update_hw_stats(p);
1544 
1545 	/* compat_mode being true specifies a call that is supposed
1546 	 * to add additional backward compatibility statistic TLVs.
1547 	 */
1548 	if (compat_mode) {
1549 		if (p->type == TCA_OLD_COMPAT)
1550 			err = gnet_stats_start_copy_compat(skb, 0,
1551 							   TCA_STATS,
1552 							   TCA_XSTATS,
1553 							   &p->tcfa_lock, &d,
1554 							   TCA_PAD);
1555 		else
1556 			return 0;
1557 	} else
1558 		err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
1559 					    &p->tcfa_lock, &d, TCA_ACT_PAD);
1560 
1561 	if (err < 0)
1562 		goto errout;
1563 
1564 	if (gnet_stats_copy_basic(&d, p->cpu_bstats,
1565 				  &p->tcfa_bstats, false) < 0 ||
1566 	    gnet_stats_copy_basic_hw(&d, p->cpu_bstats_hw,
1567 				     &p->tcfa_bstats_hw, false) < 0 ||
1568 	    gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 ||
1569 	    gnet_stats_copy_queue(&d, p->cpu_qstats,
1570 				  &p->tcfa_qstats,
1571 				  p->tcfa_qstats.qlen) < 0)
1572 		goto errout;
1573 
1574 	if (gnet_stats_finish_copy(&d) < 0)
1575 		goto errout;
1576 
1577 	return 0;
1578 
1579 errout:
1580 	return -1;
1581 }
1582 
1583 static int tca_get_fill(struct sk_buff *skb, struct tc_action *actions[],
1584 			u32 portid, u32 seq, u16 flags, int event, int bind,
1585 			int ref, struct netlink_ext_ack *extack)
1586 {
1587 	struct tcamsg *t;
1588 	struct nlmsghdr *nlh;
1589 	unsigned char *b = skb_tail_pointer(skb);
1590 	struct nlattr *nest;
1591 
1592 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
1593 	if (!nlh)
1594 		goto out_nlmsg_trim;
1595 	t = nlmsg_data(nlh);
1596 	t->tca_family = AF_UNSPEC;
1597 	t->tca__pad1 = 0;
1598 	t->tca__pad2 = 0;
1599 
1600 	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1601 	if (!nest)
1602 		goto out_nlmsg_trim;
1603 
1604 	if (tcf_action_dump(skb, actions, bind, ref, false) < 0)
1605 		goto out_nlmsg_trim;
1606 
1607 	nla_nest_end(skb, nest);
1608 
1609 	if (extack && extack->_msg &&
1610 	    nla_put_string(skb, TCA_EXT_WARN_MSG, extack->_msg))
1611 		goto out_nlmsg_trim;
1612 
1613 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1614 
1615 	return skb->len;
1616 
1617 out_nlmsg_trim:
1618 	nlmsg_trim(skb, b);
1619 	return -1;
1620 }
1621 
1622 static int
1623 tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
1624 	       struct tc_action *actions[], int event,
1625 	       struct netlink_ext_ack *extack)
1626 {
1627 	struct sk_buff *skb;
1628 
1629 	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1630 	if (!skb)
1631 		return -ENOBUFS;
1632 	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
1633 			 0, 1, NULL) <= 0) {
1634 		NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1635 		kfree_skb(skb);
1636 		return -EINVAL;
1637 	}
1638 
1639 	return rtnl_unicast(skb, net, portid);
1640 }
1641 
1642 static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
1643 					  struct nlmsghdr *n, u32 portid,
1644 					  struct netlink_ext_ack *extack)
1645 {
1646 	struct nlattr *tb[TCA_ACT_MAX + 1];
1647 	const struct tc_action_ops *ops;
1648 	struct tc_action *a;
1649 	int index;
1650 	int err;
1651 
1652 	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1653 					  tcf_action_policy, extack);
1654 	if (err < 0)
1655 		goto err_out;
1656 
1657 	err = -EINVAL;
1658 	if (tb[TCA_ACT_INDEX] == NULL ||
1659 	    nla_len(tb[TCA_ACT_INDEX]) < sizeof(index)) {
1660 		NL_SET_ERR_MSG(extack, "Invalid TC action index value");
1661 		goto err_out;
1662 	}
1663 	index = nla_get_u32(tb[TCA_ACT_INDEX]);
1664 
1665 	err = -EINVAL;
1666 	ops = tc_lookup_action(tb[TCA_ACT_KIND]);
1667 	if (!ops) { /* could happen in batch of actions */
1668 		NL_SET_ERR_MSG(extack, "Specified TC action kind not found");
1669 		goto err_out;
1670 	}
1671 	err = -ENOENT;
1672 	if (__tcf_idr_search(net, ops, &a, index) == 0) {
1673 		NL_SET_ERR_MSG(extack, "TC action with specified index not found");
1674 		goto err_mod;
1675 	}
1676 
1677 	module_put(ops->owner);
1678 	return a;
1679 
1680 err_mod:
1681 	module_put(ops->owner);
1682 err_out:
1683 	return ERR_PTR(err);
1684 }
1685 
1686 static int tca_action_flush(struct net *net, struct nlattr *nla,
1687 			    struct nlmsghdr *n, u32 portid,
1688 			    struct netlink_ext_ack *extack)
1689 {
1690 	struct sk_buff *skb;
1691 	unsigned char *b;
1692 	struct nlmsghdr *nlh;
1693 	struct tcamsg *t;
1694 	struct netlink_callback dcb;
1695 	struct nlattr *nest;
1696 	struct nlattr *tb[TCA_ACT_MAX + 1];
1697 	const struct tc_action_ops *ops;
1698 	struct nlattr *kind;
1699 	int err = -ENOMEM;
1700 
1701 	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1702 	if (!skb)
1703 		return err;
1704 
1705 	b = skb_tail_pointer(skb);
1706 
1707 	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1708 					  tcf_action_policy, extack);
1709 	if (err < 0)
1710 		goto err_out;
1711 
1712 	err = -EINVAL;
1713 	kind = tb[TCA_ACT_KIND];
1714 	ops = tc_lookup_action(kind);
1715 	if (!ops) { /*some idjot trying to flush unknown action */
1716 		NL_SET_ERR_MSG(extack, "Cannot flush unknown TC action");
1717 		goto err_out;
1718 	}
1719 
1720 	nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
1721 			sizeof(*t), 0);
1722 	if (!nlh) {
1723 		NL_SET_ERR_MSG(extack, "Failed to create TC action flush notification");
1724 		goto out_module_put;
1725 	}
1726 	t = nlmsg_data(nlh);
1727 	t->tca_family = AF_UNSPEC;
1728 	t->tca__pad1 = 0;
1729 	t->tca__pad2 = 0;
1730 
1731 	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1732 	if (!nest) {
1733 		NL_SET_ERR_MSG(extack, "Failed to add new netlink message");
1734 		goto out_module_put;
1735 	}
1736 
1737 	err = __tcf_generic_walker(net, skb, &dcb, RTM_DELACTION, ops, extack);
1738 	if (err <= 0) {
1739 		nla_nest_cancel(skb, nest);
1740 		goto out_module_put;
1741 	}
1742 
1743 	nla_nest_end(skb, nest);
1744 
1745 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1746 	nlh->nlmsg_flags |= NLM_F_ROOT;
1747 	module_put(ops->owner);
1748 	err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1749 			     n->nlmsg_flags & NLM_F_ECHO);
1750 	if (err < 0)
1751 		NL_SET_ERR_MSG(extack, "Failed to send TC action flush notification");
1752 
1753 	return err;
1754 
1755 out_module_put:
1756 	module_put(ops->owner);
1757 err_out:
1758 	kfree_skb(skb);
1759 	return err;
1760 }
1761 
1762 static int tcf_action_delete(struct net *net, struct tc_action *actions[])
1763 {
1764 	int i;
1765 
1766 	for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1767 		struct tc_action *a = actions[i];
1768 		const struct tc_action_ops *ops = a->ops;
1769 		/* Actions can be deleted concurrently so we must save their
1770 		 * type and id to search again after reference is released.
1771 		 */
1772 		struct tcf_idrinfo *idrinfo = a->idrinfo;
1773 		u32 act_index = a->tcfa_index;
1774 
1775 		actions[i] = NULL;
1776 		if (tcf_action_put(a)) {
1777 			/* last reference, action was deleted concurrently */
1778 			module_put(ops->owner);
1779 		} else  {
1780 			int ret;
1781 
1782 			/* now do the delete */
1783 			ret = tcf_idr_delete_index(idrinfo, act_index);
1784 			if (ret < 0)
1785 				return ret;
1786 		}
1787 	}
1788 	return 0;
1789 }
1790 
1791 static int
1792 tcf_reoffload_del_notify(struct net *net, struct tc_action *action)
1793 {
1794 	size_t attr_size = tcf_action_fill_size(action);
1795 	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {
1796 		[0] = action,
1797 	};
1798 	const struct tc_action_ops *ops = action->ops;
1799 	struct sk_buff *skb;
1800 	int ret;
1801 
1802 	skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1803 			GFP_KERNEL);
1804 	if (!skb)
1805 		return -ENOBUFS;
1806 
1807 	if (tca_get_fill(skb, actions, 0, 0, 0, RTM_DELACTION, 0, 1, NULL) <= 0) {
1808 		kfree_skb(skb);
1809 		return -EINVAL;
1810 	}
1811 
1812 	ret = tcf_idr_release_unsafe(action);
1813 	if (ret == ACT_P_DELETED) {
1814 		module_put(ops->owner);
1815 		ret = rtnetlink_send(skb, net, 0, RTNLGRP_TC, 0);
1816 	} else {
1817 		kfree_skb(skb);
1818 	}
1819 
1820 	return ret;
1821 }
1822 
1823 int tcf_action_reoffload_cb(flow_indr_block_bind_cb_t *cb,
1824 			    void *cb_priv, bool add)
1825 {
1826 	struct tc_act_pernet_id *id_ptr;
1827 	struct tcf_idrinfo *idrinfo;
1828 	struct tc_action_net *tn;
1829 	struct tc_action *p;
1830 	unsigned int act_id;
1831 	unsigned long tmp;
1832 	unsigned long id;
1833 	struct idr *idr;
1834 	struct net *net;
1835 	int ret;
1836 
1837 	if (!cb)
1838 		return -EINVAL;
1839 
1840 	down_read(&net_rwsem);
1841 	mutex_lock(&act_id_mutex);
1842 
1843 	for_each_net(net) {
1844 		list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
1845 			act_id = id_ptr->id;
1846 			tn = net_generic(net, act_id);
1847 			if (!tn)
1848 				continue;
1849 			idrinfo = tn->idrinfo;
1850 			if (!idrinfo)
1851 				continue;
1852 
1853 			mutex_lock(&idrinfo->lock);
1854 			idr = &idrinfo->action_idr;
1855 			idr_for_each_entry_ul(idr, p, tmp, id) {
1856 				if (IS_ERR(p) || tc_act_bind(p->tcfa_flags))
1857 					continue;
1858 				if (add) {
1859 					tcf_action_offload_add_ex(p, NULL, cb,
1860 								  cb_priv);
1861 					continue;
1862 				}
1863 
1864 				/* cb unregister to update hw count */
1865 				ret = tcf_action_offload_del_ex(p, cb, cb_priv);
1866 				if (ret < 0)
1867 					continue;
1868 				if (tc_act_skip_sw(p->tcfa_flags) &&
1869 				    !tc_act_in_hw(p))
1870 					tcf_reoffload_del_notify(net, p);
1871 			}
1872 			mutex_unlock(&idrinfo->lock);
1873 		}
1874 	}
1875 	mutex_unlock(&act_id_mutex);
1876 	up_read(&net_rwsem);
1877 
1878 	return 0;
1879 }
1880 
1881 static int
1882 tcf_del_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1883 	       u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1884 {
1885 	int ret;
1886 	struct sk_buff *skb;
1887 
1888 	skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1889 			GFP_KERNEL);
1890 	if (!skb)
1891 		return -ENOBUFS;
1892 
1893 	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
1894 			 0, 2, extack) <= 0) {
1895 		NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes");
1896 		kfree_skb(skb);
1897 		return -EINVAL;
1898 	}
1899 
1900 	/* now do the delete */
1901 	ret = tcf_action_delete(net, actions);
1902 	if (ret < 0) {
1903 		NL_SET_ERR_MSG(extack, "Failed to delete TC action");
1904 		kfree_skb(skb);
1905 		return ret;
1906 	}
1907 
1908 	ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1909 			     n->nlmsg_flags & NLM_F_ECHO);
1910 	return ret;
1911 }
1912 
1913 static int
1914 tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
1915 	      u32 portid, int event, struct netlink_ext_ack *extack)
1916 {
1917 	int i, ret;
1918 	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1919 	struct tc_action *act;
1920 	size_t attr_size = 0;
1921 	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1922 
1923 	ret = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
1924 					  extack);
1925 	if (ret < 0)
1926 		return ret;
1927 
1928 	if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
1929 		if (tb[1])
1930 			return tca_action_flush(net, tb[1], n, portid, extack);
1931 
1932 		NL_SET_ERR_MSG(extack, "Invalid netlink attributes while flushing TC action");
1933 		return -EINVAL;
1934 	}
1935 
1936 	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1937 		act = tcf_action_get_1(net, tb[i], n, portid, extack);
1938 		if (IS_ERR(act)) {
1939 			ret = PTR_ERR(act);
1940 			goto err;
1941 		}
1942 		attr_size += tcf_action_fill_size(act);
1943 		actions[i - 1] = act;
1944 	}
1945 
1946 	attr_size = tcf_action_full_attrs_size(attr_size);
1947 
1948 	if (event == RTM_GETACTION)
1949 		ret = tcf_get_notify(net, portid, n, actions, event, extack);
1950 	else { /* delete */
1951 		ret = tcf_del_notify(net, n, actions, portid, attr_size, extack);
1952 		if (ret)
1953 			goto err;
1954 		return 0;
1955 	}
1956 err:
1957 	tcf_action_put_many(actions);
1958 	return ret;
1959 }
1960 
1961 static int
1962 tcf_add_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1963 	       u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1964 {
1965 	struct sk_buff *skb;
1966 
1967 	skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1968 			GFP_KERNEL);
1969 	if (!skb)
1970 		return -ENOBUFS;
1971 
1972 	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
1973 			 RTM_NEWACTION, 0, 0, extack) <= 0) {
1974 		NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1975 		kfree_skb(skb);
1976 		return -EINVAL;
1977 	}
1978 
1979 	return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1980 			      n->nlmsg_flags & NLM_F_ECHO);
1981 }
1982 
1983 static int tcf_action_add(struct net *net, struct nlattr *nla,
1984 			  struct nlmsghdr *n, u32 portid, u32 flags,
1985 			  struct netlink_ext_ack *extack)
1986 {
1987 	size_t attr_size = 0;
1988 	int loop, ret, i;
1989 	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1990 	int init_res[TCA_ACT_MAX_PRIO] = {};
1991 
1992 	for (loop = 0; loop < 10; loop++) {
1993 		ret = tcf_action_init(net, NULL, nla, NULL, actions, init_res,
1994 				      &attr_size, flags, 0, extack);
1995 		if (ret != -EAGAIN)
1996 			break;
1997 	}
1998 
1999 	if (ret < 0)
2000 		return ret;
2001 	ret = tcf_add_notify(net, n, actions, portid, attr_size, extack);
2002 
2003 	/* only put existing actions */
2004 	for (i = 0; i < TCA_ACT_MAX_PRIO; i++)
2005 		if (init_res[i] == ACT_P_CREATED)
2006 			actions[i] = NULL;
2007 	tcf_action_put_many(actions);
2008 
2009 	return ret;
2010 }
2011 
2012 static const struct nla_policy tcaa_policy[TCA_ROOT_MAX + 1] = {
2013 	[TCA_ROOT_FLAGS] = NLA_POLICY_BITFIELD32(TCA_ACT_FLAG_LARGE_DUMP_ON |
2014 						 TCA_ACT_FLAG_TERSE_DUMP),
2015 	[TCA_ROOT_TIME_DELTA]      = { .type = NLA_U32 },
2016 };
2017 
2018 static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
2019 			 struct netlink_ext_ack *extack)
2020 {
2021 	struct net *net = sock_net(skb->sk);
2022 	struct nlattr *tca[TCA_ROOT_MAX + 1];
2023 	u32 portid = NETLINK_CB(skb).portid;
2024 	u32 flags = 0;
2025 	int ret = 0;
2026 
2027 	if ((n->nlmsg_type != RTM_GETACTION) &&
2028 	    !netlink_capable(skb, CAP_NET_ADMIN))
2029 		return -EPERM;
2030 
2031 	ret = nlmsg_parse_deprecated(n, sizeof(struct tcamsg), tca,
2032 				     TCA_ROOT_MAX, NULL, extack);
2033 	if (ret < 0)
2034 		return ret;
2035 
2036 	if (tca[TCA_ACT_TAB] == NULL) {
2037 		NL_SET_ERR_MSG(extack, "Netlink action attributes missing");
2038 		return -EINVAL;
2039 	}
2040 
2041 	/* n->nlmsg_flags & NLM_F_CREATE */
2042 	switch (n->nlmsg_type) {
2043 	case RTM_NEWACTION:
2044 		/* we are going to assume all other flags
2045 		 * imply create only if it doesn't exist
2046 		 * Note that CREATE | EXCL implies that
2047 		 * but since we want avoid ambiguity (eg when flags
2048 		 * is zero) then just set this
2049 		 */
2050 		if (n->nlmsg_flags & NLM_F_REPLACE)
2051 			flags = TCA_ACT_FLAGS_REPLACE;
2052 		ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, flags,
2053 				     extack);
2054 		break;
2055 	case RTM_DELACTION:
2056 		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2057 				    portid, RTM_DELACTION, extack);
2058 		break;
2059 	case RTM_GETACTION:
2060 		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2061 				    portid, RTM_GETACTION, extack);
2062 		break;
2063 	default:
2064 		BUG();
2065 	}
2066 
2067 	return ret;
2068 }
2069 
2070 static struct nlattr *find_dump_kind(struct nlattr **nla)
2071 {
2072 	struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
2073 	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
2074 	struct nlattr *kind;
2075 
2076 	tb1 = nla[TCA_ACT_TAB];
2077 	if (tb1 == NULL)
2078 		return NULL;
2079 
2080 	if (nla_parse_deprecated(tb, TCA_ACT_MAX_PRIO, nla_data(tb1), NLMSG_ALIGN(nla_len(tb1)), NULL, NULL) < 0)
2081 		return NULL;
2082 
2083 	if (tb[1] == NULL)
2084 		return NULL;
2085 	if (nla_parse_nested_deprecated(tb2, TCA_ACT_MAX, tb[1], tcf_action_policy, NULL) < 0)
2086 		return NULL;
2087 	kind = tb2[TCA_ACT_KIND];
2088 
2089 	return kind;
2090 }
2091 
2092 static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
2093 {
2094 	struct net *net = sock_net(skb->sk);
2095 	struct nlmsghdr *nlh;
2096 	unsigned char *b = skb_tail_pointer(skb);
2097 	struct nlattr *nest;
2098 	struct tc_action_ops *a_o;
2099 	int ret = 0;
2100 	struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
2101 	struct nlattr *tb[TCA_ROOT_MAX + 1];
2102 	struct nlattr *count_attr = NULL;
2103 	unsigned long jiffy_since = 0;
2104 	struct nlattr *kind = NULL;
2105 	struct nla_bitfield32 bf;
2106 	u32 msecs_since = 0;
2107 	u32 act_count = 0;
2108 
2109 	ret = nlmsg_parse_deprecated(cb->nlh, sizeof(struct tcamsg), tb,
2110 				     TCA_ROOT_MAX, tcaa_policy, cb->extack);
2111 	if (ret < 0)
2112 		return ret;
2113 
2114 	kind = find_dump_kind(tb);
2115 	if (kind == NULL) {
2116 		pr_info("tc_dump_action: action bad kind\n");
2117 		return 0;
2118 	}
2119 
2120 	a_o = tc_lookup_action(kind);
2121 	if (a_o == NULL)
2122 		return 0;
2123 
2124 	cb->args[2] = 0;
2125 	if (tb[TCA_ROOT_FLAGS]) {
2126 		bf = nla_get_bitfield32(tb[TCA_ROOT_FLAGS]);
2127 		cb->args[2] = bf.value;
2128 	}
2129 
2130 	if (tb[TCA_ROOT_TIME_DELTA]) {
2131 		msecs_since = nla_get_u32(tb[TCA_ROOT_TIME_DELTA]);
2132 	}
2133 
2134 	nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
2135 			cb->nlh->nlmsg_type, sizeof(*t), 0);
2136 	if (!nlh)
2137 		goto out_module_put;
2138 
2139 	if (msecs_since)
2140 		jiffy_since = jiffies - msecs_to_jiffies(msecs_since);
2141 
2142 	t = nlmsg_data(nlh);
2143 	t->tca_family = AF_UNSPEC;
2144 	t->tca__pad1 = 0;
2145 	t->tca__pad2 = 0;
2146 	cb->args[3] = jiffy_since;
2147 	count_attr = nla_reserve(skb, TCA_ROOT_COUNT, sizeof(u32));
2148 	if (!count_attr)
2149 		goto out_module_put;
2150 
2151 	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
2152 	if (nest == NULL)
2153 		goto out_module_put;
2154 
2155 	ret = __tcf_generic_walker(net, skb, cb, RTM_GETACTION, a_o, NULL);
2156 	if (ret < 0)
2157 		goto out_module_put;
2158 
2159 	if (ret > 0) {
2160 		nla_nest_end(skb, nest);
2161 		ret = skb->len;
2162 		act_count = cb->args[1];
2163 		memcpy(nla_data(count_attr), &act_count, sizeof(u32));
2164 		cb->args[1] = 0;
2165 	} else
2166 		nlmsg_trim(skb, b);
2167 
2168 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
2169 	if (NETLINK_CB(cb->skb).portid && ret)
2170 		nlh->nlmsg_flags |= NLM_F_MULTI;
2171 	module_put(a_o->owner);
2172 	return skb->len;
2173 
2174 out_module_put:
2175 	module_put(a_o->owner);
2176 	nlmsg_trim(skb, b);
2177 	return skb->len;
2178 }
2179 
2180 static int __init tc_action_init(void)
2181 {
2182 	rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, 0);
2183 	rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, 0);
2184 	rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
2185 		      0);
2186 
2187 	return 0;
2188 }
2189 
2190 subsys_initcall(tc_action_init);
2191